This invention relates in general to exercising apparatus and deals more particularly with an improved compact, user-manipulated exercise machine of the cable type wherein resistive force is provided by a spring mechanism.
It is generally desirable that a workout with a user-manipulated exercise machine provide substantially the same benefits as a workout with free weights. To achieve this goal it is essential that the exercise machine provide a resistive output force of substantially constant magnitude which must be overcome by counterforce applied by the user. This objective is easily achieved in large stationary machines, as, for example, machines of the weight stack type. However, the attainment of this goal has proven elusive in the development of light weight compact exercise machines intended for home use.
Independent exercising of both sides of the body promotes symmetrical development and reduces the magnitude of the resistance force required. Less resistance force is required, because without the stabilizing influence of an interconnecting bar, each arm is able to support significantly less than 1/2 the load used for barbell exercises. This "dumbbell" approach, when applied to an exercise machine, reduces the magnitude of the resistive output force which the machine is required to produce, thereby enabling reduction in the size and weight of the machine.
Accordingly, it is the general aim of the invention to provide an improved durable, lightweight, compact exercise machine of the cable type, which includes cable wound on a reel and provides a force output of substantially constant magnitude both in the cable extension and cable retraction modes. Another aim of the invention to provide a machine having two independently operably, simultaneously adjustable force outputs which may be used in the performance of a wide variety of exercise in standing, sitting, rowing and reclining positions. A further aim of the invention is to incorporate in an exercise machine common, inexpensive springs as the resistive load, which springs historically have been unsuitable for this purpose due to their linearly increasing (non-constant) output force in the direction which draws cable from the reel.